DE102014224540A1 - Release bearing with thrust washer - Google Patents

Abstract

The invention relates to a release bearing (10) for a motor vehicle clutch, comprising an inner ring (12) and an outer ring (14) arranged coaxially and radially therebetween, between which rolling elements (22) are arranged, wherein the outer ring (14) has a radially inwardly directed annular ring Flange (28), on the rolling body distal axial front side (32) a thrust washer (34) is arranged. According to the invention, at least three axial projections (40), which are received in respectively associated openings (46) of the flange (28) of the outer ring (14), are formed on the roller-side rear side (38) of the thrust washer (34). By the front side on the outer ring (14) taking place axially fixing the thrust washer (34) results in a reliable axial attachment of the thrust washer (34) while reducing the necessary radial space, thereby at the same time a more efficient self-centering of the release bearing (10) is made possible.

Description

The invention relates to a release bearing for a motor vehicle clutch, with an inner ring and a coaxially and radially outer ring arranged therebetween, between which rolling elements are arranged, wherein the outer ring has a radially inwardly directed annular flange, on the rolling body remote axial front side a thrust washer is arranged.

In motor vehicles, dry disc clutches are used primarily for the drive-related separation of a transmission from an internal combustion engine, in particular when the transmission ratio of the transmission is to be adapted to the current operating state of the internal combustion engine. In order to perform a coupling operation as low as possible and with a low operating force, release bearing for clutches used in motor vehicles are usually equipped with thrust washers, via which a diaphragm spring is in contact with a bearing ring of the release bearing.

The DE 10 2006 040 463 A1 shows and describes such a clutch release bearing with a thrust washer. The thrust washer of this clutch release bearing has an L-shaped cross-sectional geometry with a circumferential, radially outwardly directed flange and extending in the axial direction tubular portion. The tubular portion of the thrust washer is receivable in a central passage opening of a radially inwardly facing flange of the inner ring of the release bearing. For axial attachment of the thrust washer radially outwardly directed locking means are formed on the tubular portion of the thrust washer, which engage behind in the inserted state of the thrust washer radially inwardly directed projections on the central passage opening of the flange of the inner ring. The thrust washer is made of a thermoplastic material, preferably based on a highly heat-resistant polyamide or other highly heat-resistant thermoplastic materials.

A disadvantage of this clutch release bearing that results in a cross-sectional reduction of the passage opening of the flange of the inner ring of the clutch release bearing through the tubular portion of the thrust washer, resulting in a given inner diameter to increased radial space requirement. Furthermore, in this known construction, a deterioration of the ability of the clutch release bearing for self-centering result.

The invention is therefore based on the object to present a release bearing for a clutch with a reliable axial connection of the thrust washer to a bearing ring and a comparatively small space requirement, at the same time a conflict with the Selbstzentrierungsfunktionalität the release bearing should be excluded.

The invention is based on the recognition that the necessary radial installation space of a thrust washer can be reduced by a frontal connection with a radially inwardly facing flange of the outer ring of a release bearing. The object is therefore achieved by a release bearing with the features of claim 1. Advantageous developments are defined in the subclaims.

The invention therefore relates to a release bearing for a motor vehicle clutch, with an inner ring and a coaxial and radially outer ring arranged therebetween, between which rolling elements are arranged, wherein the outer ring has a radially inwardly directed annular flange, on the rolling body remote axial front side a thrust washer is arranged. To achieve the object, it is provided in this release bearing that at the rolling body near the rear of the thrust washer at least three axial projections are formed, which are accommodated in respectively associated openings of the flange of the outer ring.

As a result, a reliable axial position securing the thrust washer is ensured on the outer ring of the release bearing while minimizing the necessary radial space. At the same time a rotation of the thrust washer is achieved with respect to the outer ring.

According to an advantageous embodiment, it is provided in this release bearing, that the at least three projections circumferentially evenly spaced from each other at the rear of the thrust washer are arranged, and that the at least three openings circumferentially equally spaced apart in the radial flange of the outer ring are arranged. As a result, a tilt-safe and at the same time secure against rotation of the thrust washer is ensured on the flange of the outer ring of the release bearing.

According to another embodiment, the projections are designed as substantially cylindrical pins and the openings as cylindrical through holes. As a result, a light and large-scale production of the release bearing can be realized.

In a favorable embodiment, it is provided that the longitudinal axes of the pins each extend parallel to the longitudinal axis of the release bearing. As a result, the thrust washer can be easily attached in the axial direction of the flange of the outer ring of the release bearing.

Another favorable development of the release bearing provides that the thrust washer has a substantially cylindrical passage opening whose inner surface is approximately flush with an inner surface of a cylindrical passage opening of the radial flange of the outer ring. This results in a reduced radial space. In addition, the self-centering of the release bearing remains unaffected. The passage opening and the passage opening of the release bearing are each formed centrally to the longitudinal axis of the release bearing.

Further, it is preferably provided that the axial length of the pins of the thrust washer is equal to or greater than the axial thickness of the radial flange of the outer ring. As a result, in addition to the pressing or gluing the pins of the thrust washer further connection techniques can be used. As a result of fixing the position, inter alia, unintentional dropping of the thrust washer during transport or during installation of the release bearing in a clutch of a motor vehicle is avoided.

According to another preferred embodiment, the pins are glued and / or pressed into the bores of the radial flange of the outer ring. As a result, a structurally particularly simple attachment possibility of the thrust washer is used on the flange of the outer ring.

A further embodiment provides that snap hooks for latching to the radial flange of the outer ring are respectively formed at the free axial end of the pins. As a result, a manufacturing technology particularly simple and fast mounting of the thrust washer is given to the flange of the outer ring of the release bearing.

Alternatively, it can be provided that the pins each have a thickening at its free axial end, which are formed by melting and / or axial compression of the free axial ends of the pins. As a result, a particularly reliable, in particular vibration-resistant, form-fitting attachment of the thrust washer is given on the flange of the outer ring of the release bearing.

The pins and the thrust washer are preferably formed integrally from a plastic. As a result, a particularly efficient production using an injection molding process is possible. In addition, the plastic material ensures low-wear and comfortable engagement and disengagement operations of the clutch. The plastic material is preferably a high heat resistant thermoplastic with an optional fiber reinforcement.

To further explain the invention, the description is accompanied by a drawing. In this shows

1 3 a partial axial section through a first embodiment of a release bearing for a clutch with a thrust washer,

2 a partial axial section through a second embodiment of a release bearing for a clutch with a thrust washer, and

3 an axial partial section through a third embodiment of a release bearing for a clutch with a thrust washer.

Accordingly, shows 1 a partial section through a first embodiment of a release bearing for a clutch with a thrust washer. The release bearing 10 has an inner ring 12 and outer ring 14 on, with the outer ring 14 coaxial with the inner ring 12 and is arranged radially above it. The inner ring 12 and the outer ring 12 . 14 are centric to a common longitudinal axis 16 the release bearing 10 arranged. On the inner ring 12 and on the outer ring 14 are facing each other and slightly concave raceways 18 . 20 formed on which a variety of spherical rolling elements 22 roll.

At the rolling body distal axial end 24 of the outer ring 14 which is a diaphragm spring 26 a clutch, not shown, facing, is a radially inwardly directed, circumferential and approximately annular flange 28 with a cylindrical passage opening here 30 educated. On one of the diaphragm spring 26 facing and thus rolling body distant annular front 32 of the flange 28 is a substantially hollow cylindrical thrust washer 34 also coaxial with respect to the longitudinal axis 16 arranged. The diaphragm spring 26 or their radially inwardly directed legs are to optimize the actuation behavior of the clutch on a likewise annular, wälzkörperfernen front 36 the thrust washer 34 axially.

At an annular and rolling close to the rear side 38 the thrust washer 34 is an axial projection 40 integrally formed, here exemplified as a cylindrical pin 42 is executed, and its longitudinal axis 44 parallel to the longitudinal axis 16 the release bearing 10 runs. The free axial end 56 of the pin 42 points from the diaphragm spring 26 path. In addition to that as a journal 42 executed axial projection 40 are at least two further, not shown here, axial projections or pins with an identical structure for the axial positional fixation of the thrust washer 34 on the outer ring 14 the release bearing 10 intended. The at least three projections or pins are on the circumference of the release bearing 10 Preferably spaced evenly distributed to each other at the roller near the rear side 38 the thrust washer 34 educated.

The axial projections 40 are each in an associated opening 46 in the radial flange 28 of the outer ring 14 the release bearing 10 added. The openings 46 are exemplary here as cylindrical holes 48 realized, in which the respective associated pin 42 are included. This is between the holes 48 and the respective pin 42 preferably at least a slight interference fit.

The thrust washer 34 according to 1 has a cylindrical passage opening 50 on, its inner surface 52 approximately flush with an inner surface 54 the passage opening 30 of the flange 28 of the outer ring 14 followed. The axial length L of the pin 42 and that of all other pins is equal to or greater than the material thickness D of the flange 28 of the outer ring 14 the release bearing 10 ,

At the free axial end 56 the pin 42 Here are just two examples of snap hooks 58 . 60 for latching connection of the thrust washer 34 with the flange 28 of the outer ring 14 educated. There may also be three or more snap hooks at the free axial end 56 the respective pin 42 be provided. When inserting the pins 42 in the assigned holes 48 are the snap hooks 58 . 60 in radial depressions at the free axial end 56 the respective pin 42 on and close flush with its unsigned outer surface. After complete insertion of the pins 42 through the associated holes 48 spread the snap hooks 58 . 60 in a radially outwardly directed pivoting movement and so come to the rolling close to the rear side 62 of the flange 28 of the outer ring 14 to the plant. In addition, the pins can 42 still in the holes 48 glued or pressed.

As a result, a permanently durable and mechanically sufficient loadable axial attachment of the thrust washer 34 on the outer ring 14 the release bearing 10 under all operating conditions of the coupling, especially at high ambient temperatures and / or vibrations ensured. At the same time is the thrust washer 34 during storage and assembly of the release bearing 10 secured against falling off the same. In addition, due to the positive snap connection, a fast, tool-free and therefore cost-effective installation of the thrust washer 34 on the outer ring 14 the release bearing 10 possible.

The thrust washer 34 is preferably made with a thermoplastic high performance plastic such as a high heat resistant polyamide or other high heat resistant thermoplastic such as a polyacryletherketone. To increase the wear resistance and service life of the thrust washer 34 of plastic with a fiber reinforcement can be reinforced, for example carbon fibers or aramid fibers ^®.

2 shows an axial partial section through a second embodiment of a release bearing 70 for a clutch with a thrust washer 74 , In this second embodiment of a release bearing 70 are the bearing rings 12 . 14 with their careers 18 . 20 for the rolling elements 22 identical design as the release bearing 10 according to 1 , In the radially inwardly directed flange 28 In turn, at least three, designed as cylindrical holes openings are introduced, of which also only one as a bore 48 trained opening 46 is shown.

Unlike the first embodiment according to 1 are at the of the diaphragm spring 26 opposite rear side 72 the thrust washer 74 at least three as cones 76 formed axial projections 78 arranged at the respective free axial end 80 however, here only by way of example rivet-like or spherical segment-shaped thickening 82 is trained. The longitudinal axis 84 the preferred one-piece on the thrust washer 74 trained pin 76 also runs parallel to the longitudinal axis 16 the release bearing 10 and is thus perpendicular to the roller near the back 72 the thrust washer 74 ,

A radially inwardly formed cylindrical passage opening 86 at the thrust washer 74 in turn closes flush with the passage opening 30 of the radial flange 28 of the outer ring 14 at. At the thrust washer 74 In turn, at least three circumferentially equally spaced pins are formed, of which only one as a pin 76 trained lead 78 you can see. These cones 76 are in the associated, congruent holes 46 . 48 in the radial flange 28 added.

The rivulet-like thickening 82 the pin 76 For example, by plasticizing the free axial end 80 the pin 76 and its subsequent transformation by means of a suitable tool. Covered after cooling the respective nietkopfartige thickening 82 in the radial direction, the associated cylindrical bore 48 and lies at the same time on the inside, close to the roller body 62 of the flange 28 of the outer ring 14 the release bearing 70 at. By a cooling process after plasticizing the pins 76 becomes an axial shrinkage movement of the free axial end 80 and the nietkopfartigen thickening 82 causes, so the thrust washer 72 with a high mechanical force against the flange 28 is pulled and creates an extremely resilient connection. Accordingly, with all other pins, not shown 76 method.

3 shows an axial partial section through a third embodiment of a release bearing with a thrust washer 94 , In this third embodiment of a release bearing 90 Almost all bearing components are identical in construction to the release bearings 10 . 70 of the 1 and 2 , Only the thrust washer 94 and their attachment to the radial flange 28 of the outer ring 14 are different. So are in the radially inwardly directed flange 28 of the outer ring 14 again at least three as cylindrical holes 48 executed openings 46 brought in. Instead of through holes, however, these can also be designed as blind holes in this embodiment.

In contrast to the two embodiments explained above are on the rolling body near the rear 92 the thrust washer 94 at least three as cones 96 formed axial projections 98 formed, which over its entire length L up to a free axial end 100 have a constant circular cross-section, that are formed continuously cylindrical. The longitudinal axis 102 the preferred one-piece with the thrust washer 94 trained cones 96 again runs parallel to the longitudinal axis 16 the release bearing 90 and is thus perpendicular to the roller near the back 92 the thrust washer 94 , The axial length L of the pins 96 here is about the same size as the material thickness D of the radial flange 28 of the outer ring 14 so that the axial end 100 the pin 98 flush with the back 62 of the flange 28 of the outer ring 14 the release bearing 90 concludes. A radially inwardly formed cylindrical passage opening 104 the thrust washer 94 also closes flush with the passage opening in this embodiment 30 of the flange 28 at.

At the thrust washer 94 In turn, at least three circumferentially equally spaced pins are formed, of which only one as a projection 98 decorated cones 96 is shown, which is also in correspondence with the pin 96 trained and these associated holes 48 in the flange 28 are receivable. The axial attachment of the pins 96 in the assigned holes 48 can be done for example by gluing or cold shrinking, the pins 96 during cold shrinkage in relation to the respectively associated bore 48 are formed with a slight oversize. For gluing the pins 96 It may be necessary to perform this with a slight undersize to a narrow annular gap for receiving a defined volume of adhesive between the respective bore 48 and the associated pin 96 to accomplish.

Alternatively, the cylindrical pins 96 with a slight oversize in relation to the diameter of the associated bore 48 be executed, so that an axial position securing the thrust washer 94 on the outer ring 14 by pressing in the pin 96 into the holes 48 can take place under training of press fits. As a result, a reliable and in particular vibration-resistant attachment of the thrust washer 94 on the outer ring 14 the release bearing 90 feasible, however, which is associated with increased assembly costs in the production.

Due to the invention always frontal connection of the thrust washer to the outer ring results in all embodiments of the release bearing reliable axial positional fixation of the thrust washer with a simultaneous reduction of the necessary radial space in the respective passage opening of the thrust washer and the passage opening of the flange of the outer ring of the release bearing, whereby at the same time a more effective self-centering of the release bearing is achieved.

LIST OF REFERENCE NUMBERS

10

 Release bearing (first variant)

12

 inner ring

14

 outer ring

16

 Longitudinal axis of the release bearing

18

 Raceway of the inner ring

20

 Raceway of the outer ring

22

 rolling elements

24

 End of the outer ring

26

 diaphragm spring

28

 Flange on the outer ring

30

 Through opening in the flange of the outer ring

32

 Front of the flange on the outer ring

34

 thrust washer

36

Rolling element remote front side of the thrust washer 34

38

Wälzkörpernahe rear of the thrust washer 34

40

Axial projection on the thrust washer 34

42

Pin on the thrust washer 34

44

Longitudinal axis of the pin 42

46

 Opening in the flange of the outer ring

48

 Cylindrical bore in the outer ring

50

 Cylindrical access opening of the thrust washer

52

 Radial inner surface of the access opening

54

 Radial inner surface of the flange

56

Free axial end of the pin 42

58

Snap hook of the pin 42

60

Snap hook of the pin 42

62

Wälzkörpernahe back of the flange 28

70

 Release bearing (second variant)

72

Wälzkörpernahe rear of the thrust washer 72

74

 thrust washer

76

Pin on the thrust washer 74

78

Axial projection on the thrust washer 74

80

Free axial end of the pin 76

82

 Nietkopfartige thickening

84

Longitudinal axis of the pin 76

86

Cylindrical access opening of the thrust washer 74

90

 Release bearing (third variant)

92

Wälzkörpernahe rear of the thrust washer 94

94

 thrust washer

96

Pin on the thrust washer 94

98

Projection on the thrust washer 94

100

Free axial end of the pin 94

102

Longitudinal axis of the pin 94

104

Cylindrical access opening of the thrust washer 94

L

 Length of the pin

D

 Material thickness of the flange

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102006040463 A1 [0003]

Claims (10)

Release bearing ( 10 . 70 . 90 ) for a motor vehicle clutch, with an inner ring ( 12 ) and a coaxial and radially disposed outer ring ( 14 ) between which rolling elements ( 22 ) are arranged, wherein the outer ring ( 14 ) a radially inwardly directed annular flange ( 28 ), at the rolling body distal axial front side ( 32 ) a thrust washer ( 34 . 74 . 94 ), characterized in that on the rolling body near the rear side ( 38 . 72 . 92 ) of the thrust washer ( 34 . 74 . 94 ) at least three axial projections ( 40 . 78 . 98 ) are formed, which in each associated openings ( 46 ) of the flange ( 28 ) of the outer ring ( 14 ) are included. Release bearing ( 10 . 70 . 90 ) according to claim 1, characterized in that the at least three projections ( 40 . 78 . 98 ) circumferentially equally spaced from each other at the back ( 38 . 72 . 92 ) of the thrust washer ( 34 . 74 . 94 ) are arranged, and that the at least three openings ( 46 ) circumferentially evenly spaced apart in the flange ( 28 ) of the outer ring ( 14 ) are formed. Release bearing ( 10 . 70 . 90 ) according to claim 1 or 2, characterized in that the projections ( 40 . 78 . 98 ) as a cylindrical pin ( 42 . 76 . 96 ) and the openings ( 46 ) as cylindrical bores ( 48 ) are formed. Release bearing ( 10 . 70 . 90 ) according to one of claims 1 to 3, characterized in that longitudinal axes ( 44 . 84 . 102 ) the pin ( 42 . 76 . 96 ) each parallel to a longitudinal axis ( 16 ) of the release bearing ( 10 ). Release bearing ( 10 . 70 . 90 ) according to one of claims 1 to 4, characterized in that the thrust washer ( 34 . 74 . 94 ) radially inside a cylindrical passage opening ( 50 . 86 . 104 ) whose inner surface ( 52 ) flush with an inner surface ( 54 ) of a cylindrical passage opening ( 30 ) of the flange ( 28 ) of the outer ring ( 14 ). Release bearing ( 10 . 70 . 90 ) according to one of claims 3 to 5, characterized in that an axial length (L) of the pins ( 42 . 76 . 96 ) is equal to or greater than the material thickness (D) of the flange ( 28 ) of the outer ring ( 14 ). Release bearing ( 90 ) according to one of claims 3 to 6, characterized in that the pins ( 96 ) into the holes ( 48 ) of the flange ( 28 ) of the outer ring ( 28 ) are glued and / or pressed. Release bearing ( 10 ) according to one of claims 3 to 6, characterized in that the free axial end ( 56 ) the pin ( 42 ) each snap hook ( 58 . 60 ) for locking with the flange ( 28 ) of the outer ring ( 14 ) having. Release bearing ( 70 ) according to one of claims 3 to 6, characterized in that the pins ( 76 ) each a thickening ( 82 ), which by melting and / or axial compression of each free axial end ( 80 ) the pin ( 76 ) can be formed. Release bearing ( 10 . 70 . 90 ) according to one of claims 3 to 9, characterized in that the pins ( 42 . 76 . 96 ) and the thrust washer ( 34 . 74 . 94 ) are integrally formed of plastic.

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